SEOUL, Jan. 9 (Yonhap) -- One out of four chief executives at South Korea's 500 largest companies were outsourced, a market research firm said Wednesday.

As of Friday, there were a total of 657 CEOs at the country's leading firms. Of the total, the career histories of 566 are known, and of those, 25.3 percent, or 143, were recruited from outside the company,

CEO Score said in a statement.

Corporate logos of South Korea's leading companies (Yonhap)

The latest findings showed 51.8 percent, or 293, of the 566 CEOs reached the top position through promotions and 23 percent, or 130, were family members of the owner, it said.

Executives who worked for Samsung Group affiliates are most preferred for the CEO positions at other local conglomerates, the latest report showed.(Yonhap)